1. Field of the Invention
The present invention relates generally to pour spouts and more particularly to a pour spout adapted to be inserted into an opening in a liquid container so that liquids can be poured from the container in a smooth flowing manner.
2. Description of the Prior Art
It is many times difficult to pour a liquid smoothly from a container due to the fact that as the liquid is being removed from the container, air must be introduced to the container at the same rate and through the same opening to replace the liquid. Since the flow of the liquid and the air is interrupted by the counter currents of the two fluids, an irregular flow of liquid results. Not only does the irregular or uneven flow deter from the speed with which the liquid is removed from the container but it is also very annoying and sometimes messy as the liquid does not flow smoothly from the container. Rather, it lurches from the container in an intermittent pattern.
To overcome the drawbacks of irregular flow, numerous systems have been devised for incorporation into the opening of a container so that air is permitted to flow into the container at the same rate as liquid flows out. An example of such a device is disclosed in U.S. Pat. No. 2,812,113 issued to Beall, Jr. on Nov. 5, 1957. This device includes a central opening through which liquid can be poured and an outer elongated tubular member which protrudes a substantial distance into the container for permitting air to flow into the container as the liquid flows out. The invention is disclosed in several embodiments wherein the device can be screwed onto a threaded neck of a container or inserted in a friction fit manner into the opening from the container. A similar device defining a variation from that disclosed in the afore-noted Beall, Jr. patent is shown in another patent to Beall, Jr., U.S. Pat. No. 2,915,223, dated Dec. 1, 1959.
Another spout adapted to avoid uneven flow is shown in U.S. Pat. No. 2,796,205 issued to Kuzma on Jun. 18, 1957. In this device, there are two outlets from an insert that is frictionally inserted into the opening of a container, and each outlet has a curved tubular member connected thereto. The curved tubular members extend in opposite directions within the container so that according to the teaching in the patent, regardless of the angle of the container as liquid is being poured therefrom, air can be introduced to the container through one tube as the liquid is removed from the container through the other tube.
Other examples of pour spouts adapted to cooperate with containers to avoid irregular flow are disclosed in British Patent Specification No. 775,066 of Brune which was published May 15, 1957; U.S. Pat. No. 3,098,586 issued to Wasserberg on Jul. 23, 1963; and U.S. Pat. No. 3,595,421 issued to Sanchis on Jul. 27, 1971.
One noticeable drawback with the pour spouts disclosed in the prior art is the fact that they have been designed for use in bottle-type containers having elongated necks so that the spout can be inserted a substantial distance into the neck of the container and be structurally retained therein by the relatively long cylindrical inner wall of the neck of the container. Other containers, such as many drum-type containers, do not have elongated necks through which the contents of the container can be poured, but rather are merely provided with an opening in the thin top wall of the container that usually has a short peripheral rim therearound. In such containers, an elongated cylindrical surface is not present for confining or gripping a pour spout that may be inserted therein, and accordingly, the pour spouts of the prior art are not felt to be satisfactory for use on many drum-type containers.
Further, none of the prior art pour spouts attach to the container to which they are fit in such a manner that the engagement is inaccessible from the outside. In effect, the attachments shown in the prior art do not lock the pour spout to the container.
Pouring liquids from many drum-type containers is subject to uneven flow, however, and accordingly, there is a need for a smooth pouring flow spout that is adapted to attach to openings in short necked containers so that liquids can be poured smoothly from the containers.
Prior art pour spouts do not include means for locking and sealing the pour spout to the container so that any effort to tamper with the contents is resisted or can be detected. The pour spout of the present invention is locked and sealed onto the container with a sealing membrane attached over a passage through which liquid flows. The pour spout remains sealed and locked onto the container until it is ready to be used.
It is to satisfy the needs herein defined and to overcome the shortcomings in the prior art that the present invention has been developed.